docs: def enq(self, task):
          """
          Enqueues a fetch task to the pool of workers. This will raise
          a RuntimeError if the pool is stopped or in the process of
          stopping.
  
          :param task: the Task object
          :type task: Task or PutTask
          """
          if not self._stop.is_set():
              self._inq.put(task)
          else:
              raise RuntimeError("Attempted to enqueue an operation while "
                                 "multi pool was shutdown!")